Michael Andrew Lennig

All Publications

• The Hemodynamic Effects of Protamine in Pediatric Patients Undergoing Pulmonary Artery Reconstruction and Unifocalization Surgery: A Pilot StudyHemodynamic Effects of Protamine in Children. Journal of cardiothoracic and vascular anesthesia Li, X., Fang, Z. A., Lennig, M. M., Klein, A., Char, D., Giustini, A. J., Boltz, M. G., Quiñónez, Z. A. 2024

  Abstract

  To determine protamine administration increases pulmonary artery pressures (PAPs) in patients undergoing unifocalization or pulmonary artery reconstruction surgeries.Retrospective database study.A large pediatric heart center within an academic quaternary care facility.All patients undergoing pulmonary artery reconstruction or a unifocalization procedure identifiable within the data warehouse.We collected data from Stanford University's data repository, formatted it, and analyzed it using RStudio (v 2023.06.1+524).Our primary outcome is the change in PAP after the administration of protamine. Secondary outcomes include changes in the mean arterial pressure, the ratio of systolic pulmonary artery to systemic artery pressure, right-sided filling pressure, and left atrial pressure. After a protamine bolus, we found a difference in PAP (Friedman χ2 = 49.46; p < 0.001). When compared with 2 minutes before its administration, the PAP was higher at 2 minutes (29.00 mmHg versus 25.00 mmHg; p < 0.001), 5 minutes (30.00 mmHg versus 25.00 mmHg; p < 0.001) and 10 minutes (31 mmHg versus 25 mmHg; p < 0.001). When coadministered with calcium, there was also a significant increase in PAP (Friedman χ2 = 28.11; p < 0.001), with a higher PAP 10 minutes after calcium administration when compared with 2 minutes before (32 mmHg versus 26 mmHg; p < 0.001).Protamine administration led to a small increase in PAP after separation from cardiopulmonary bypass in patients undergoing pulmonary artery reconstruction or unifocalization surgeries. Calcium coadministration did not lead to a greater increase in PAP.

  View details for DOI 10.1053/j.jvca.2024.11.001

  View details for PubMedID 39592272

• The Hemodynamic Effects of Bolus Dose Calcium in Patients Undergoing Pulmonary Artery Reconstruction and Unifocalization Surgery: A Pilot Study. Journal of cardiothoracic and vascular anesthesia Quiñónez, Z. A., Klein, A., Li, X., Lennig, M. A., Giustini, A. J., Boltz, M. G., Char, D. 2024

  Abstract

  To determine if bolus administration of calcium increases pulmonary artery pressures after unifocalization procedures or pulmonary artery reconstruction surgery.Retrospective cohort study using Stanford University's data warehouse.A large pediatric heart center within an academic quaternary care facility.All patients undergoing pulmonary artery reconstruction or unifocalization procedures identifiable in the data warehouse.Data were collected from Stanford University's data repository and formatted and analyzed using RStudio (v 2023.06.1+524).The primary outcome was the change in pulmonary artery systolic pressure (PASP) after a bolus administration of calcium. Secondary endpoints include changes in pulmonary arterial-to-systemic arterial pressure ratio, mean arterial pressure, right-sided filling pressure, and left atrial pressure. The Friedman test was used to assess differences and the Durbin-Conover rank-sum for pairwise comparisons. A difference in PASP after a bolus dose of calcium was found (Friedman X2 = 13.67, p = 0.003), with a higher PASP 5 minutes after calcium administration compared with 2 minutes before administration (35 mmHg v 33 mmHg, p = 0.01), and a higher PASP 10 minutes after calcium administration compared with2 minutes before administration (35 mmHg v 33 mmHg, p = 0.008).Calcium bolus administration led to an increase in pulmonary arterial pressure in patients after pulmonary artery reconstruction or unifocalization surgeries. It may be prudent to avoid bolus administration in this patient population immediately after repair or in patients with right ventricular dysfunction.

  View details for DOI 10.1053/j.jvca.2024.08.008

  View details for PubMedID 39227189

• Geospatial Analysis of the Proportion of Persons Defined as Underrepresented in Medicine for Each Medical School and Their Surrounding Core-Based Statistical Area. Health equity Quiñónez, Z. A., Benitez-Melo, A., Diaz, L. M., Lennig, M., Char, D., Smith, C. 2024; 8 (1): 132-137

  Abstract

  The current approach to increasing diversity in medical education fails to consider local community demographics when determining medical school matriculation.We propose that medical schools better reflect their surrounding community, both because racially/ethnically concordant physicians have been shown to provide better care and to repair the historical and current racist impacts of these institutions that have criminalized, displaced, and excluded local Black and Brown communities.In this study, we used geospatial analysis to determine that medical school enrollments generally fail to reflect their surrounding community, represented as their core-based statistical area, within which the individual medical schools reside.

  View details for DOI 10.1089/heq.2023.0221

  View details for PubMedID 38435025

  View details for PubMedCentralID PMC10908325

• Acute Hemodynamics in the Fontan Circulation: Open-Label Study of Vasopressin. Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies Adamson, G. T., Yu, J., Ramamoorthy, C., Peng, L. F., Taylor, A., Lennig, M., Schmidt, A. R., Feinstein, J. A., Navaratnam, M. 2023

  Abstract

  OBJECTIVE: To describe the acute hemodynamic effect of vasopressin on the Fontan circulation, including systemic and pulmonary pressures and resistances, left atrial pressure, and cardiac index.DESIGN: Prospective, open-label, nonrandomized study (NCT04463394).SETTING: Cardiac catheterization laboratory at Lucile Packard Children's Hospital, Stanford.PATIENTS: Patients 3-50 years old with a Fontan circulation who were referred to the cardiac catheterization laboratory for hemodynamic assessment and/or intervention.INTERVENTIONS: A 0.03 U/kg IV (maximum dose 1 unit) bolus of vasopressin was administered over 5 minutes, followed by a maintenance infusion of 0.3 mU/kg/min (maximum dose 0.03 U/min).MEASUREMENTS AND MAIN RESULTS: Comprehensive cardiac catheterization measurements before and after vasopressin administration. Measurements included pulmonary artery, atrial, and systemic arterial pressures, oxygen saturations, and systemic and pulmonary flows and resistances. There were 28 patients studied. Median age was 13.5 (9.1, 17) years, and 16 (57%) patients had a single or dominant right ventricle. Following vasopressin administration, systolic blood pressure and systemic vascular resistance (SVR) increased by 17.5 (13.0, 22.8) mm Hg (Z value -4.6, p < 0.001) and 3.8 (1.8, 7.5) Wood Units (Z value -4.6, p < 0.001), respectively. The pulmonary vascular resistance (PVR) decreased by 0.4±0.4 WU (t statistic 6.2, p < 0.001), and the left atrial pressure increased by 1.0 (0.0, 2.0) mm Hg (Z value -3.5, p < 0.001). The PVR:SVR decreased by 0.04±0.03 (t statistic 8.1, p < 0.001). Neither the pulmonary artery pressure (median difference 0.0 [-1.0, 1.0], Z value -0.4, p = 0.69) nor cardiac index (0.1±0.3, t statistic -1.4, p = 0.18) changed significantly. There were no adverse events.CONCLUSIONS: In Fontan patients undergoing cardiac catheterization, vasopressin administration resulted in a significant increase in systolic blood pressure, SVR, and left atrial pressure, decrease in PVR, and no change in cardiac index or pulmonary artery pressure. These findings suggest that in Fontan patients vasopressin may be an option for treating systemic hypotension during sedation or general anesthesia.

  View details for DOI 10.1097/PCC.0000000000003326

  View details for PubMedID 37462430

• Transnasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) augments oxygenation in children with cyanotic heart disease during microdirect laryngoscopy and bronchoscopy JOURNAL OF CLINICAL ANESTHESIA Caruso, T. J., Sidell, D. R., Lennig, M., Menendez, M., Fonseca, A., Rodriguez, S. T., Tsui, B. 2019; 56: 53–54

  View details for DOI 10.1016/j.jclinane.2019.01.029

  View details for Web of Science ID 000468713500021

• Assessment of the Reconstructed Pulmonary Circulation With Lung Perfusion Scintigraphy After Unifocalization and Repair of Tetralogy of Fallot With Major Aortopulmonary Collaterals WORLD JOURNAL FOR PEDIATRIC AND CONGENITAL HEART SURGERY Wise-Faberowski, L., Irvin, M., Lennig, M., Long, J., Nadel, H. R., Bauser-Heaton, H., Asija, R., Hanley, F. L., McElhinney, D. B. 2019; 10 (3): 313–20

  View details for DOI 10.1177/2150135119836735

  View details for Web of Science ID 000470668700010